Engine



p 1945. w. G. GERNANDT 2,384,461

ENGINE Filed Jan. 7. 1944 52 J as 25' IN VEN TOR.

Mlle G. Germwmi Patented Sept. 1i, i945 UNITED 'STATES PATENT OFFICEENGINE Waldo G. Gernandt, Detroit, Mic asaignor to Briggs ManufacturingCompany, Detroit, Mich, a corporation of Michigan Application January I,1944, Serial No. 517,381

19 Claims.

This invention relates to internal combustion engines and particularlyto engines of the type having rotatable valves associated with thecylinders thereof and usually mounted in the cylinder heads of theengines. The present invention has particular although not exclusiveapplication to an internal combustion engine of the kind in which therotatable valve in the head, preferably although not necessarily of thekind which rotates continuously in one direction, is formed withsubstantially all or at least the major portion of the combustionchamber and is generally conical or frusto-conical in shape. Thecombustion chamber within the rotor or rotary valve has an opening atone end leading to the cylinder and a second opening preferably at aside thereof adapted to communicate during operation with an outlet orinlet passage, or both, as the case may be, and the combustible chargewithin the combustion chamber is fired preferably by spark ignition.

The present invention contemplates as one of its important objects theeiiicicnt cooling of engines of the foregoing type as also the provisionof means for controlling the expansion of portions of the cylinder headadjacent the rotatable valve so as to maintain more closely oraccurately the desired operating clearances between the valve andrelated bearing surfaces on the cylinder head. v p

A further object of the invention is to provide an engine having arotatable valve and improved means for controlling the relativeexpansion of the valve and cylinder head due to heating of associatedportions thereof during operation.

Another obiect of the invention is to provide an engine having acylinder, cylinder head and arotatablevalveinthehead,suchasasenersllyfrusto-conical valve, and in which means are provided for maintainingclosely predetermined operating cl between the valve and head.especiallywherethevaiveandheadaremadeof metals or megi alloys havingdifferent thermal It is also an object of the inventionto provide anengine having a cylinderhead and evolve rotatable therein and having adiiferent. such as a smaller, coeiiicient of expansion than the head andin which means is provided whereby the rateoferpansionoftheheadwiilbesubstantiailythesameasthevalveatcertainbearinglocaiities where it is desirable tomaintain uniform operatingclsarancesbetweentheccoperatingbearingluri'acsscfthevalveandhead.

the following description and appended claims. reference being had tothe accompanying drawing forming a part of this specification whereinlike reference characters designate corresponding parts in the severalviews.

Fig. 1 is a fragmentary sectional elevation illustrating a portion of amulti-cylinder engine embodying the present invention.

Fig. 2 is a transverse section taken substantially through lines 2-! ofFig. 1 looking in the direction of the arrows.

Fig. 3 is an enlarged fragmentary section illustrating the portion ofFig. l appearing within the circle.

Before explaining in detail the present invention it is to be understoodthat the invention is not limited in its application to the details ofconstruction and arrangement of parts illustrated in the a mpany sdrawin since the invention is capable of other embodiments and of beingpracticed or carried out in various ways. Also it is to be understoodthat the phraseology or terminology employed herein is for the purposeof description and not of limitation.

Referring to the drawing, the present engine comprises a cylinder flwithin which a suitable piston II is mounted for reciprocation. Thepiston is connected in the usual manner through a wrist pin 2! to thecrankshaft (not shown) of the engine. Surrounding the cylinder ill is acylindrical Jacket II which is rigidly secured to the crankcase or formssubstantially a portion of the crankcase of the engine. This jacketmember it extends substantially the height of the cylinder and is spacedfrom the wall of the cylinder to provide a water cooling space orchamber 25 extending entirely around the cylinder.

The engine is provided with a cylinder head It which is cast to providea valve housing portion i'l provided with a generally frusto-conicalcavity or recess. as hereinafter described, for receiving the rotaryvalve. The cylinder head i also cast to provide a cylinder head jacketII spaced from the valve housing 81. The liquid cooling space or chamberIt forms a continuation of the chamber II. When the cylinder head isassembled the lower edge of the jacket portion 28 is drawn down tightlyagainst the upper edge of the cylinder Jacket N, there being a gasket llinterpos d between the iuxtaposed surfaces of these portions adapted tobe compressed to provide a liquidtisht joint.

The lower or inner edge of the valve housing portion ll of the cylinderhead is formed with an Othsrobiectsofthisinvsntionwiliappesrinsnnularboss orthickensdportlon lLandthis ortion is formed with anannular groove or reass 82 to receive an expansion control ring 13. 'hisring preferably has a tight or press lit withl. the recess or groove 82and the outer face of ie ring extends substantially flush with the uterface or the enlarged portion ll of the valve ousing II. The upper edgeokgzhe cylinder til Itcnds in abutting relation to that portion of thewe: edge of the valve housing 21 which lies inardly oi the expansioncontrol ring 38, and inerposed between the cylinder and valve housing anannular gasket II. This gasket may be of ie copper-asbestos type capableof sustaining lgh temperatures and pressure. and when the linder head isdrawn down tightly this s et ill provide a liquid and gas-tight Joint.In order lat a gasket 84 of maximum width may be used 1d at the sametime to avoid excessive restrican of the liquid passage between thechambers i and II, the expansion control ring 3! sets enrely into therecess l! in the valve housing and notched at Ila around its lower inneredge to 'ovlde clearance for the gasket ring 8|. The cylinder head isformed with a series or as or ribs 38 and 31 bored to receive bolts 3|tending from bosses (not shown) on the Jacket ember 24 which, as stated,is fixed to the crankse. The cylinder head may be drawn down :htly tothe crankcase or jacket 2| by suitable its applied to the upper ends ofthe bolts 38, us connecting the Jackets 24 and 2! tightly tother at thewater tight Joint formed by the sket Ill. The cylinder head is formedwith a generally isto-conical recess III within which is mountedrotatable valve or rotor II which is also of genally rrusto-conicalconstruction having taperoutwardly converging walls correspondingnerally in shape to the inner walls 01' the recess The bottom or innerwall Ha of the valve is eierably tapered so as to correspond substaniiyto the taper of the piston head, the conuction being such that thepiston head will proach very closely the bottom oi the valve 4! en thepiston is at the outer end of its stroke. The valve member I is formedwith a side port communicating with the combustion chamber and adaptedto register successively during roion of the valve with a spark plug 44,an ex- 1st passage or conduit ll, and an intake con- .t or passage II inthe cylinderhead, the direcn of rotation of the valve being indicated byi arrow in Fig. 3. As also shown in this figure. liquid coolant chamber20 has extensions 290 the cylinder head extending substantially und thevalve member ll and also extending ng and in the helsht oi the outerwalls 01 the must and intake passages 48 and 40. Another tion 29b of thecoolant chamber extends push the dividing wall between these passages.-m this construction it will be seen that subntially all portions of thecylinder, cylinder .d, valve and intake and exhaust passages, on aresubjected to heating during operation, exposed to the cooling effect oithe liquid ulated through the water Jackets. The coolis preferablyintroduced into the lower end of chamber 26, circulated upwardly throughthe imunicating chambers, which have a common at in the cylinder head. a1 addition to the side port It the valve Ii has :ntral port or opening41 at its inner end comiicating with the cylinder. The valve member salso formed with a cooling chamber 4! exiing entirely around thecombustion chamber 01' the valve member. This cooling chamber is adaptedto receive any suitable cooling medium such, for example, as metallicsodium, which is sealed into the chamber by means of an expanding plug"a.

In the present embodiment the valve or rotor 4| is driven at pne haliengine or crankshalt speed. It is provided with a projecting stem 48through the medium of which the driving mechanism for the valve isconnected. The valve housing portion 21 of the cylinder head is providedwith an annular recess 50 in its outer end through which the valve stem4! extends. Within this recess is located a cup-shaped spring retainermember Ill adapted to receive a compression spring 52 surrounding thevalve stem 49. The outer end of the spring engages a steel coupling diskII. This disk is formed centrally thereof with an annular set of teethI! meshing with corresponding teeth i'ormed on the end of the valve stem4!. The valve stem is tapped to receive a threaded stud or bolt 58 whichcarries a nut 56a engageable with the coupling disk 53 and adapted to betightened to draw down the disk and maintain its teeth 54 in constantmesh with the teeth on the outer end of the valve stem. The spring I2is, therefore, held under constant compression so as to yieldingly holdthe valve upwardly within the rrusto-conicai recess ll in the valvehousing. The strength of a this spring and the amount of preloadingthereof is such that the efiort exerted by the spring to raise the valvewithin the valve housing is suilicient to substantially offset or equalthe effort exerted during the suction stroke oi the piston to draw thevalve downwardly and away from its seat.

The coupling disk It is provided with external teeth 55 meshing withinternal teeth Illa on a ring gear 51. This gear in turn has externalteeth 51b meshing with the teeth of a valve driving gear 58 secured to alongitudinally extending top shaft Ill. The cylinder head is formed witha housing 69 provided with a removable closure 60 for housing thedriving mechanism located in the cylinder head. The top shaft 6| may bedriven from the crankshaft oi the engine in the manner shown anddescribed in application Serial No. 515,479, filed December 24, 1943.

The valve member is also preferably provided with an exterior reliefarea 10 extending entirely around the valve and substantially the heightof the side port 43. This annular relief area may be formed either inthe valve or in the wall 40 of the valve housing and may be constructedand serve the purposes in accordance with my copending applicationSerial No. 405,260, flied July 19, 1943.

In accordance with the present invention the ring 33 is adapted torestrain or control the expansion of the wall portion II o! the cylinderhead during operation of the engine so as to maintain within closelimits the desired operating clearance between the inner end oi thevalve and the valve housing I1. It will be understood that the bearingsurfaces of the valve II and housing 21 above and below the reliei area10 are suitably lubricated in order to maintain a him of oil betweenthese suriaces. It is. therefore, important that the operating clearancebetween these surfaces be held constant and be prevented from increasingappreciably since otherwise there will result an undesirable loss oflubricating oil due to oil being drawn into the cylinder during thesuction stroke of the piston.

The expansion control ring a is preterably formed of a metal or metalalloy selected so that by virtue of its differential expansion rate thehead portion 3i will expand at substantially the same rate as theadjacent portion of the cone valve. Where the head is made oi! analuminum alloy the ring 33 will be made of a metal or metallic alloyhaving a coefllcient of expansion less than that of the aluminum alloyof the head but not less than that of the valve. For example, if thecylinder head is formed of aluminum and the valve of cast iron, the ringmay be made of steel. In such case the expansion rate of the ring willbe considerably less than that or the head but somewhat greater thanthat of the valve. This is desirable since the valve becomes hottest atits inner end and tends, on account of its higher temperature, to expandat this locality more than the adjacent portion ll of the head. Thus,with an aluminum head and a valve of cast iron or other ferrous metal,it is preferred that the ring 33 have a thermal expansion rate less thanthat of the head but somewhat greater than that of the valve, especialiyin view of the fact that the ring is maintained at a lower temperatureby being exposed directly to the coolant in the jacketed chamber 29.

I claim:

1. In an internal combustion engine, a c'ylinder, a cylinder head, arotatable valve in said head, said valve and head having diflerentcoeillcients of thermal expansion, said valve and head having adjacentwall portions in operative engagement, and means ior varying the rate ofexpansion of said portion of the head so as to conform more closely tothe rate of expansion of said portion of the valve.

2. In an internal combustion engine, a cylinder, a cylinder head, arotatable valve in said head, said valve and head having differentcoeflicients of thermal expansion, said valve and head having adjacentwall portions in operative engagement, and means for reducing the rateof expansion of said portion of the head so as to conform more closelyto the rate of expansion of said portion of the valve.

3. In an internal combustion engine, a cylinder, 8. cylinder head, arotatable valve in said head, said valve having a lesser coeflieient ofthermal expansion than the head, said valve and head having adjacentwall portions in operative engagement, and means for restrainingexpansion said portion of the head relative to said adjacent portion ofthe valve.

4. In an internal combustion engine, a cylinder, a cylinder head, arotatable valve in said head, said valve having a lesser coefiicient ofthermal expansion than the head, said valve and head having adjacentwall portions in operative engagement, and means for reducing the rateof expansion of said portion oi the head so as to conform more closelyto the rate of expansion of said adjacent portion of the valve.

5. In an internal combustion engine, a cylinder, a cylinder head, arotatable valve in said head. said valve and head having diflerentcoefllcients of thermal expansion, said valve and head having adjacentwall portions in operative engagement, and means carried by the head forvarying the rate of said expansion of a portion or the head so as toconform more closely to the rate of expansion of said adjacent portionof the valve.

8. In an internal combustion engine, a cylinder, 9. cylinder head, arotatable valve in said head, said valve having a lesser coeflicient ofthermal expansion than the head, said valve and head baring adjacentwall portions in operative engagement, and means carried by the head forrestraining expansion of said portion of the head relative to saidadjacent portion of the valve.

'7. In an internal combustion engine, a cylinder, a cylinder head, arotatable valve in said head, said valve having a lesser coefllcient 0!thermal expansion than the head, said valve and head having adjacentwall portions in operative engagement, and a expansion control ringengaging said wall por on of the head for restraining expansion thereofrelative to said adjacent portion of the valve.

8. In an internal combustion engine, a cylinder, a cylinder head, arotatable valve in said head, said valve having a lesser coefilcient ofthermal expansion than the head, said valve and head having adjacentwall portions in operative engagement, and an expansion control ringhaving a lesser coeflicient of expansion than the head for restrainingexpansion of said portion thereof relative to said adjacent portion ofthe valve.

9. In an internal combustion engine, a cylinder, a cylinder head, arotatable valve in said head, said valve and head having adjacent wallsin operative engagement, and an expansion control ring engaging saidwall of the head for varying its rate of thermal exp'ansion with respectto that oi the valve.

10. In an internal combustion engine, a cylinder, a cylinder head, arotatable valve in said head, said valve and head having adjacent wallsin operative engagement, and an expansion contrel ring engaging saidwall of the head and carried thereby for varying its rate 01 thermalexpansion with respect to that of the valve.

11. In an internal combustion engine, a cylinder, a cylinder head, arotatable valve in said head, said valve and head having adjacent wallsin operative engagement, and an expansion. control ring engaging saidwall oi the head for reducing its rate of thermal expansion with respectto that of the valve.

12. In an internal combustion engine, a cylinder, 2:. cylinder head, arotatable valve in said head, said valve and head having adjacent wallsin operative engagement, and expansion control means engaging said wallof the head for modi- Iying its rate of thermal expansion with respectto that of the valve.

13. In an internal combustion engine, a cylinder, a cylinder head, arotatable generally frustoconical valve in said head, said valve andhead having adjacent walls in operative engagement, and expansioncontrol means engaging said well of the head adjacent the inner end ofthe valve for modifying its rate of thermal expansion with respect tothat of the valve.

14. In an internal combustion engine, a cylinder, 9. cylinder head, arotatable valve in said head, said valve and head having adjacent wallsin operative engagement, and expansion control means engaging said wallof the head and having a lesser coeflicient of thermal expansion than,

the head for modifying its rate of thermal expansion with respect tothat of the valve.

15. In an internal combustion engine, a cylinder, a cylinder head, arotatablev valve in the head, and expansion control means formed ofmetal having a lesser coeflicient or thermal expansion than the head anda greater coefilcient of thermal expansion than the valve forrestraining expansion of the head relatively to the valve.

16. In an internal combustion engine, a cylinder, a cylinder head havinga portion provided with a generally trusto-conical cavity, a generallyirusto-conical valve in said cavity, said cylinder and valve beingformed of ferrous metal and said cylinder head being formed of metalhaving a greater coefllcient 0! thermal expansion, and means forrestraining lateral expansion of said head at the locality of itsbearing engagement with the valve at the inner end oi the latter, saidmeans comprising a ring engaging the head and formed of diilerent metalthan the head.

17. In an internal combustion engine, a cylinder, a cylinder head, arotatable valve in the head, a liquid coolant Jacket surrounding thevalve and its bearing portion in the head, and an expansion control ringcarried by the head adjacent the inner end 01' the valve and exposed tothe coolant in said Jacket.

Patent No. 2,581+,1r61.

18. In an internal combustion ermine, a cylinder, a cylinder head, arotatable generally i'rustoconical valve in the head, a liquid coolantjacket surrounding the valve and its bearing portion in the head, and anexpansion control ring carried by the head at the locality of itsbearing engagement with the wider end of the valve and exposed to thecoolant in said jacket.

19. In an internal combustion engine, a cylinder, a cylinder head, arotatable generally irustoconical valve in the head, a liquid coolantjacket surrounding the valve and its bearing portion in the head, and anexpansion control ring carried by the head at the locality of itsbearing engagement with the wider end of the valve and exposed to thecoolant in said Jacket, said ring being formed of metal having adifl'erent co- 4 eilicient of expansion than the head.

September 11, .1915.

WALDO G. GERNAND'I'.

It is hereby certified that error appearsin the printed specification ofthe above numbered patent requiring correction as follows: Page 3,

first column, line 70, claim 5, strike out "said"; same line and claim,

for "a" before "portion" read saidand that the said LettersPstent=should B,- ai ter "said" insert --w a11--,

' and second column, line 25, claim be read with this correction thereinthat the same may conform to the record of the case in the PatentOffice.

Signed and sealed this 5th day of February. -A. D. 19li6.

(Seal) Leslie Frazer First Assistant commissioner of Patents.

of thermal expansion than the valve for restraining expansion of thehead relatively to the valve.

16. In an internal combustion engine, a cylinder, a cylinder head havinga portion provided with a generally trusto-conical cavity, a generallyirusto-conical valve in said cavity, said cylinder and valve beingformed of ferrous metal and said cylinder head being formed of metalhaving a greater coefllcient 0! thermal expansion, and means forrestraining lateral expansion of said head at the locality of itsbearing engagement with the valve at the inner end oi the latter, saidmeans comprising a ring engaging the head and formed of diilerent metalthan the head.

17. In an internal combustion engine, a cylinder, a cylinder head, arotatable valve in the head, a liquid coolant Jacket surrounding thevalve and its bearing portion in the head, and an expansion control ringcarried by the head adjacent the inner end 01' the valve and exposed tothe coolant in said Jacket.

Patent No. 2,581+,1r61.

18. In an internal combustion ermine, a cylinder, a cylinder head, arotatable generally i'rustoconical valve in the head, a liquid coolantjacket surrounding the valve and its bearing portion in the head, and anexpansion control ring carried by the head at the locality of itsbearing engagement with the wider end of the valve and exposed to thecoolant in said jacket.

19. In an internal combustion engine, a cylinder, a cylinder head, arotatable generally irustoconical valve in the head, a liquid coolantjacket surrounding the valve and its bearing portion in the head, and anexpansion control ring carried by the head at the locality of itsbearing engagement with the wider end of the valve and exposed to thecoolant in said Jacket, said ring being formed of metal having adifl'erent co- 4 eilicient of expansion than the head.

September 11, .1915.

WALDO G. GERNAND'I'.

It is hereby certified that error appearsin the printed specification ofthe above numbered patent requiring correction as follows: Page 3,

first column, line 70, claim 5, strike out "said"; same line and claim,

for "a" before "portion" read saidand that the said LettersPstent=should B,- ai ter "said" insert --w a11--,

' and second column, line 25, claim be read with this correction thereinthat the same may conform to the record of the case in the PatentOffice.

Signed and sealed this 5th day of February. -A. D. 19li6.

(Seal) Leslie Frazer First Assistant commissioner of Patents.

